The present invention is in the field of lighting and relates more particularly to a sealed flood light, which can be used for example on an outdoor stage for shows. This floodlight is designed in such a way as to make it possible to change the color of the light emitted.
Various kinds of floodlights are known which are capable of shining a light beam which can be adjusted in intensity and which can be made to change color. This change of colour can be achieved using colored filters interposed in a beam of white light, which filters can be disposed in a ring or overlaid one above the other. It is also possible to carry out this change with an assembly of filters and of dichroic mirrors in the light beam. In practice all these systems with their advantages and drawbacks are more or less effective when they are working indoors. As soon as one wishes to use these unsealed floodlights outdoors it is necessary to find solutions for protecting them from bad weather without impairing performance. If one has unsealed floodlights, they will certainly be limited in their steering movements on account of interference with the covers provided for their own protection.
French Patent FR 908.257 presents an apparatus intended for underwater searches and characterized by an underwater floodlight forming on entirely closed assembly, completely sealed, which effectively resists the pressure of the water, even at great depths, and exhibits great mechanical robustness.
American Patent U.S. Pat. No. 5,651,606 relates to an apparatus for outdoor use which consequently is exposed to inclement weather and which is used as a floodlight with high-intensity light and as a steerable floodlight for accentuating buildings and other constructions.
The present invention aims to alleviate these difficulties. It presents a sealed floodlight, which consequently can be subjected to inclement weather, which can change colours by reason of the assembly of filters available to it and of the independent electrical supply system for each of the bulbs which it comprises.
The subject of the present invention is a sealed floodlight comprising at least one series of three bulbs placed on a circle with their respective filters and their electrical supply system placed inside a frame in the form of a shell composed of two pieces, a front piece exhibiting a bore placed in front of each bulb and closed by a glass pane secured to this front piece and another rear piece, the two pieces being joined by way of an O-ring seal; a gland being placed on the rear piece of the shell allows the passage of cables for supplying the electrical system, exhibiting a fixing rod, characterized in that it comprises a central bulb which emits yellow or white colored light, the light beams emitted by the bulbs and the central bulb being substantially parallel.
In a preferred mode of execution the filters relating to the bulbs are alternately red, green and blue. In this mode of execution, the floodlight can advantageously contain two series of three bulbs whose filters are slightly more tinted from one series to the other. These filters are placed behind the glass panes between the glass panes and each bulb so that the light beams are coloured.
The clamping of the two pieces of the shell is advantageously effected with fixing screws which collaborate to press the O-ring seal between the said pieces.
To facilitate the clamping on the inside the bulbs collaborate with their sockets which are housed in a bas which bears against a plate for separating two parts, the plate supported by the rear piece of the shell; the base and the plate are fixed by screws to the rear piece of the shell.
In one preferred embodiment the floodlight exhibits a compact shape; it can advantageously be an ovoid or a sphere.
It comprises a fixing rod with at its head a ball joint whose clamping is effected by means of the screws and of a round base which matches the shape of the ball joint.
In another mode of execution the electrical supply cables pass through the ball joint of the rod, thereby avoiding the need to have the gland in the rear part of the shell.
It is also possible to substitute the ball joint at the head of the rod with a screw and nut set together with a sealing collar.
The appended drawing represents by way of non-limiting example a preferred embodiment of the subject of the present invention as well as a variant to this first.